Answer:
x = 12.1
Step-by-step explanation:
20 − (z + 7) = 0.9
Distribute the minus sign
20 -x -7 = .9
Combine like terms
13 -x = .9
Subtract 13 from each side
-x = -12.1
x = 12.1
Y = 12x is a direct variation which is a proportion.
As x increases y also increases.
The answer to your equation is x=2.
Why? Because..................
3x*2=12
Divide both sides by 3*2
3x*2/3*3=12/3*2
Simplify
12/3*2
x=6
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